The Bollywood film industry is often distinguished by its having produced films that have almost always been "musicals" since the 1930s. As Sangeeta Gopal and Sujata Moorti note, associating the American "musical" with Hindi popular films can be misleading because many Hindi popular films elude the generic category of musical melodrama evoked by the term "musical" in its contemporary usage in other contexts.
The typical Hindi popular film blockbuster through the early 2000s was characterized by its inclusion of spectacular "song sequences," musical numbers that featured characters singing and/or dancing. The songs featured have long been used to promote the films outside the cinema hall through commercial recordings and radio broadcasts, and today they also circulate via both audio and audiovisual formats including Internet streaming, digital downloads, television programming, and DVD and VCD compilations. Song sequences often featured inventive choreography, scenic locations, and extravagant costumes alongside compelling lyrics and memorable music that made them the highlight of most commercially successful films.
The production standards of song sequences, already one of the most expensive parts of a film's production, were further enhanced by the unprecedented financing enabled by india's economic liberalization policies during the 1990s. During this era the Bombay film industry transformed into the globalized industry now known as Bollywood and attracted new international audiences. (Just last month, Richard Corliss from TIME cited Sanjay Leela Bhansali's 2002 film Devdas, a film defined by its extravagant sets and costumes-- especially in its song sequences, as one of the "10 greatest films of the millenium.")
Several recent films, especially those associated with the wave of "indie" films, have however begun to feature songs in a manner more familiar to Hollywood conventions, namely, in the background. This move away from the song sequence is motivated at least partly by their expense and the fact that their inclusion lengthen films' duration in relation to shorter length media from Hollywood and television. In its twilight, the spectacular song sequence today most often appears in self-referential contexts such as parodies that emphasize its aesthetics of excess, homages that reiterate its history, and in the case of the following sequence "Main Agar Kahoon" from Farah Khan's 2007 film Om Shanti Om, scenes that simultaneously construct and deconstruct its nostalgic appeal as the rapidly disappearing foundation of Hindi popular films.